Alarcón began his senior career withRCD Mallorca B of theTercera División. In January 2018, he went on loan toCF Platges de Calvià.[3][4] He made his debut for Mallorca on 18 August 2018 againstPoblense.[5] He would go on to score five goals in his first season with the club, the first of which was scored on 27 October 2018 as Mallorca lost 3–2 toPlatges de Calvià.[6]
In January 2020, Alarcón signed withFC Tucson ofUSL League One. He made his league debut for the club on 25 July 2020, playing the entirety of a 2–1 away victory overFort Lauderdale CF.[5] He scored his first goal on 18 August againstOrlando City B.[7] In December, FC Tucson exercised their club option on Alarcón,[5] however, prior to the season, he mutually agreed to terminate his contract at the club.[8]
In September 2021, he signed with Romanian clubUniversitatea Cluj inLiga II.[9][10] He had initially been set to joinFC Brașov, however, upper management of the club decided not to sign him after he impressed in his trial.[11][12] He made nine appearances for the club as they earned promotion to the top tier for the following season.[13] In June 2022, he was released by the club.[14]
In July 2022, Alarcón signed a contract withCanadian Premier League clubCavalry FC.[15][16] In December 2022, Cavalry announced that he would be returning for the 2023 season, and that his contract had a club option for 2024.[17] Upon completion of the 2023 season, the defender's club option for the 2024 season was declined, thus ending his time with the club.[18]
On 15 December 2023, Alarcón officially joined fellow CPL sideValour FC on afree transfer, for the 2024 season.[19][20] He made his debut on 14 April againstVancouver FC.[21] After the 2024 season, the club picked up his option for the 2025 season.[22][23]
